Imaging for quality control in an electronic cigarette

ABSTRACT

Assembly and quality of an electronic cigarette (“e-Cig”) may be tested and verified using imaging techniques. Infrared (“IR”) imaging may identify whether a temperature is uniform in an e-Cig during usage. Potential burning locations may be identified through the imaging by identifying locations whose temperature is unusually high or non-uniform. This temperature information may be used to calibrate the power of the e-Cig.

PRIORITY

This application claims priority to U.S. Provisional Application No.61/755,008, entitled “IR imaging for uniformity and correct assembly forelectronic cigarettes,” filed on Jan. 22, 2013, the entire disclosure ofwhich is hereby incorporated by reference.

BACKGROUND

An electronic cigarette (“e-cigarette” or “e-Cig”) is a device thatemulates tobacco cigarette smoking, by producing smoke replacement thatmay be similar in its physical sensation, general appearance, andsometimes flavor (i.e., with tobacco fragrance, menthol taste, addednicotine etc.). The e-Cig may include a battery portion and a cartomizerportion (i.e. “cartridge”). The battery portion of the e-Cig includes acontroller and battery for powering the device and the cartomizerportion generates an aerosol mist (i.e. e-smoke or vapor) that is areplacement for cigarette smoke. In particular, the cartomizer may useheat, ultrasonic energy, or other means to atomize/vaporize an“e-Liquid” solution (e.g. based on propylene glycol, or glycerin, forexample including taste and fragrance ingredients) into an aerosol mist.The atomization may be similar to nebulizer or humidifier vaporizingsolutions for inhalation. The cartomizer may include, or may be referredto as an atomizer, and the atomization may be caused by a heatingelement that heats the e-Liquid to generate the mist/vapor/e-smoke. Theheating element may become quite hot in order to properly heat thee-Liquid and depending on the duration of usage of the e-Cig. Excessiveheat within the e-Cig may cause burning of the internal components ofthe e-Cig. For example, burning may occur when a cartridge filled with aliquid becomes empty, such as when the liquid has evaporated or beenvaporized as part of the e-Cig smoking process. Burning may result inbad taste and less pleasure when smoking and a smoker of an e-Cig maynot be able to predict when the burning will occur. Calibration of thepower provided from the battery to the cartridge may reduce the chancesof burning.

BRIEF DESCRIPTION OF THE DRAWINGS

The system and method may be better understood with reference to thefollowing drawings and description. Non-limiting and non-exhaustiveembodiments are described with reference to the following drawings. Thecomponents in the drawings are not necessarily to scale, emphasisinstead being placed upon illustrating the principles of the invention.In the drawings, like referenced numerals designate corresponding partsthroughout the different views.

FIG. 1 is a diagram of an electronic cigarette.

FIG. 2 is a diagram of a portion of the cartridge of an electroniccigarette.

FIG. 3 is a diagram of the coil and wick for an electronic cigarette.

FIG. 4 is a diagram of an embodiment of imaging of an electroniccigarette.

FIG. 5 is a diagram of an imaging process.

FIG. 6 is a diagram of a calibration process.

DETAILED DESCRIPTION

The system and method described herein describe an electronic cigarette(“e-Cig”) testing system and method. In particular, imaging may be usedfor determining a temperature distribution of components in thecartridge, such as the coil. Excessively high temperatures ornon-uniformity of temperature may indicate a potential problem for thecartridge and can be used to calibrate the cartridge. The calibrationmay include reducing power to the cartridge to determine if thetemperature or uniformity improves. The optimal power level may then bedetermined.

Other systems, methods, features and advantages will be, or will become,apparent to one with skill in the art upon examination of the followingfigures and detailed description. It is intended that all suchadditional systems, methods, features and advantages be included withinthis description, be within the scope of the invention, and be protectedby the following claims. Nothing in this section should be taken as alimitation on those claims. Further aspects and advantages are discussedbelow.

Subject matter will now be described more fully hereinafter withreference to the accompanying drawings, which form a part hereof, andwhich show, by way of illustration, specific example embodiments.Subject matter may, however, be embodied in a variety of different formsand, therefore, covered or claimed subject matter is intended to beconstrued as not being limited to any example embodiments set forthherein; example embodiments are provided merely to be illustrative.Likewise, a reasonably broad scope for claimed or covered subject matteris intended. Among other things, for example, subject matter may beembodied as methods, devices, components, or systems. Accordingly,embodiments may, for example, take the form of hardware, software,firmware or any combination thereof (other than software per se). Thefollowing detailed description is, therefore, not intended to be takenin a limiting sense.

Throughout the specification and claims, terms may have nuanced meaningssuggested or implied in context beyond an explicitly stated meaning.Likewise, the phrase “in one embodiment” as used herein does notnecessarily refer to the same embodiment and the phrase “in anotherembodiment” as used herein does not necessarily refer to a differentembodiment. It is intended, for example, that claimed subject matterinclude combinations of example embodiments in whole or in part.

In general, terminology may be understood at least in part from usage incontext. For example, terms, such as “and”, “or”, or “and/or,” as usedherein may include a variety of meanings that may depend at least inpart upon the context in which such terms are used. Typically, “or” ifused to associate a list, such as A, B or C, is intended to mean A, B,and C, here used in the inclusive sense, as well as A, B or C, here usedin the exclusive sense. In addition, the term “one or more” as usedherein, depending at least in part upon context, may be used to describeany feature, structure, or characteristic in a singular sense or may beused to describe combinations of features, structures or characteristicsin a plural sense. Similarly, terms, such as “a,” “an,” or “the,” again,may be understood to convey a singular usage or to convey a pluralusage, depending at least in part upon context. In addition, the term“based on” may be understood as not necessarily intended to convey anexclusive set of factors and may, instead, allow for existence ofadditional factors not necessarily expressly described, again, dependingat least in part on context.

FIG. 1 is a diagram of an electronic cigarette. The “smoke” produced byan e-Cig is a created by turning an e-Liquid 110 into mist and somevapor with an atomizer 112. The e-Liquid 110 may be stored in a liquidcontainer. The cartomizer 113 may include the atomizer 112 and thee-Liquid 110. The cartomizer 113 may also be referred to as a cartridgethroughout this disclosure and may be disposable. The e-liquid 110 mayhave a high viscosity at room temperature to enable longer shelf lifeand reduce leakages; however, this high viscosity may reduce theatomization rate. The e-Liquid is atomized via airflow 108, generated bythe inhalation of the user (i.e. the smoker or consumer or vapor). Inorder to reduce the viscosity, to a level enabling atomization, externalheat may be applied through the heating element 111, which may include aheating coil and a wick that is soaked in or includes a portion of thee-Liquid 110. An exemplary heating element is shown in FIGS. 2-4. Inparticular, the heating element 111 may be a coil in one embodiment thatwraps around the wick in order to heat the liquid on the wick. Localviscosity may be reduced via heating, while inhalation occurs, enablingatomization in the inhalation-generated flow of air 108. The e-Liquid110 may be heated via an electric current flowing through the heatingelement 111 and may then be atomized and evaporated through the e-Cigand may contain tastes and aromas that create a smoking sensation. Thecontroller 102 may be activated due to airflow 108 (from the inhaledair) passing a flow sensor 104. The sensor 104 may be activated by thepressure drop across the sensor and may directly switch the battery 106power on, or be used as an input for the controller 102 that thenswitches the battery 106 current on. Although illustrated as separatefrom the e-Cig, the controller 102 may be a part of the e-Cig (e.g.along with the battery 106). The battery 106 may be a separate/removableassembly. The battery 106 may include one or more electronic chipscontrolling and communicating from it. It may connect with thecartomizer 113, which can be replaced or changed (e.g. when anew/different e-Liquid is desired).

The e-Cig may include two parts. The first part is often just referredto as the battery or battery portion (i.e. battery enclosure) and itincludes the battery cell, the airflow sensor and the controller. Thesecond part is the cartridge (i.e. cartomizer 113) includes the e-Liquidthat is required for smoke and flavor generation. In other embodiments,there may be more or fewer parts. An airflow tube of the batteryenclosure and an airflow tube of the cartridge may enable the smoker topuff through the e-Cig and activate the airflow sensor inside thebattery portion. This may trigger the controller and cause the coilinside the cartridge to get hot, evaporate the liquid that is in thecartridge and cause smoke (i.e. vapor). The battery portion may instructthe cartridge to turn on, after which the coil is heated by the powerapplied by battery side (it may use a PWM scheme for controlling theheating profile).

Although not shown in FIG. 1, the e-Cig may include connections (i.e.connectors or electrical connections) that are used for power deliveryto the heating element 111 and for charging the battery 106. Inparticular, that power delivery may be through metal connectors betweenthe battery portion and the cartridge, such as those shown and describedbelow with respect to FIGS. 3-4. The power (i.e. electrical current orelectrical power) may be calibrated based on the measured temperature ofthe e-Cig. In one embodiment, an imager 120 may take images of theheating element 111 to determine if the temperatures within a heatingelement exceed a maximum temperature of if the temperature distributionwithin the heating element is not sufficiently uniform (i.e. there arehot spots). In one embodiment, the images from the imager 120 may betaken when the airflow is in a direction opposite the labeled airflow108, such that a pump or vacuum at the battery end (e.g. near flowsensor 104) sucks air in the direction opposite labeled airflow 108.This embodiment is illustrated in and further described with respect toFIG. 4 (i.e. airflow 416). In addition, the imager 120 is also furtherdescribed below with respect to FIG. 4 (i.e. imager 410 may be the sameas or similar to imager 120). The analyzer 122 may analyze the resultingimage to identify either of the potential problematic conditions(excessively high temperature or non-uniformity of temperature). In oneembodiment, this identification may be used to calibrate the powerbecause the presence of a problematic condition may require a slightdecrease in power. The power may be decreased until the imaging revealsthat the problematic condition is reduced or eliminated.

Although not shown, the e-Cig may include a non-volatile memory ormemory chip in the cartridge. The memory chip may store informationabout the cartomizer, including the calibration information that may betransmitted to the controller 102 or battery 106 to set the power thatis transferred to the cartridge. In particular, the calibration data canbe read and conveyed to the controller (typically on the battery) thatwill apply the power regimen to the cartridge during smoking. This maybe necessary because the cartridge is interchangeable with differentbattery portions and the calibration information may need to be conveyedto each battery portion for setting the appropriate power scheme forthat particular cartridge. In another embodiment, the cartridge mayinclude a communications chip that communicates to the battery (e.g.through a controller that may be a part of the battery portion or may beexternal to the e-Cig, such as a user's smartphone or other computingdevice that is in communication with the e-Cig). In another embodimentwith a disposable e-Cig (e.g. both the cartridge and battery portion aredisposable and may be one unit), the calibration testing may occurduring production/assembly such that the calibration data may be used toset/adjust the power scheme at that time, which may eliminate the needfor storing and/or communicating the calibration data. In alternativeembodiments, the cartridge may be labeled with the calibrationinformation which can be utilized by the user for establishing the powerscheme.

FIG. 2 is a diagram of a portion of the cartridge of an electroniccigarette. FIG. 2 illustrates the heating coil 202 wrapped around a wickwhich is soaked with the e-Liquid. The heating coil is powered from thebattery and the heat from the coil then operates to at least partiallyvaporize the e-Liquid (for generating the “smoke”). Image 204illustrates an exemplary heat distribution (i.e. thermal image) of thewick and the coil. The heating coil should be below a maximumtemperature and the temperature distribution across the coil should beuniform. A thermal image should illustrate an approximately uniformdistribution of heat on the coil and the corresponding portions of thewick. In one embodiment, non-uniformity may be illustrated by “hotspots.” The hotter spots on the wick may be more sensitive to burning,and when burning-inducing conditions may occur (e.g. when liquid flow issomewhat restricted), burning may be reduced if heat transfer more even(i.e. uniform distribution of heat/temperature). Any non-uniformity inthe heating coil may exist if the temperature of a certain area of thecoil is much higher than the average of the measured temperature.

FIG. 3 is a diagram of the coil and wick for an electronic cigarette.FIG. 3 illustrates the coil wrapped around the wick. The wick mayinclude or be at least partially soaked with e-Liquid that is heatedwhen the coil is powered. The coil is powered through two connectingwires that connect with the heating coil through crimping between thewires. As described a thermal image may indicate whether the coil and/orwick are below a maximum temperature and whether the temperature isuniform. In alternative embodiments, other components of the e-Cig, suchas the crimping and connecting wires may also be imaged to check thetemperature.

FIG. 4 is a diagram of an embodiment of imaging of an electroniccigarette. The wick 402 is wrapped with the coil 404 as shown in FIG. 3with connecting wires 406, 408. The imager 410 may be the imager 120from FIG. 1. The imager 410 may be connected with an analyzer (e.g.analyzer 122 from FIG. 1) for analyzing the thermal image. The thermalimage direction 412 may be from a top portion of the heating coil 404which is down from the mouthpiece end towards the battery portion.Imaging from this angle results in a thermal image of both the heatingcoil 404 and the wick 402. During the imaging a vacuum pump 414 may belocated on an end towards the battery portion that establishes anairflow 416 that flows from the battery portion (not shown) towards thewick 402 and heating coil 404. In one embodiment, the analyzer analyzesa thermal image of the heating coil 404 to ensure the coil does notexceed a maximum temperature and to ensure that the heat distribution isuniform. In alternative embodiments, different imaging angles may beutilized for different components.

The imager 410 or 120 may be a measurement of infrared, such as infraredthermography (“IRT”), thermal imaging, or thermal video. The resultingimages may be referred to as a temperature map or a thermogram. Sincethe amount of radiation emitted by all objects increases withtemperature, the thermogram enables a visual depiction of temperaturevariation. In alternative embodiments, the imager may be an opticalsensor/camera/recorder that includes an IR filter. The optical recordingmay be less expensive but the temperature measurements may be lessaccurate than with IR thermal imaging.

FIG. 5 is a diagram of an imaging process. As described, the imagingprocess may be utilized in the assembly process for checking componentsor calibrating components. A flaw in a component may be identified basedon thermal imaging or proper calibration may improve the operation ofthe e-Cig. In block 502, the e-Cig is assembled including the cartridge(with coil, wick, and e-Liquid container). In one embodiment, theimaging is of a fully assembled e-Cig or at least a fully assembledcartridge, but in alternative embodiments, different components may beseparately tested (e.g. the coil by itself may be tested prior tocartridge assembly). The e-Liquid from the e-Liquid container is addedto the wick of the cartridge in block 504. Electrical power is thenapplied to the coil in block 506. Since the coil is powered, one or morethermal images may be taken of the assembly in block 508. As describedwith respect to FIG. 4, the thermal image may be of the coil and wicktaken from the mouthpiece of the cartridge. In block 510, the thermalimages are analyzed to determine the temperatures of components, such asthe coil. There may be a preset maximum temperature and a presetuniformity threshold that are compared with the thermal image. In oneexample, the temperature uniformity may be a requirement that thetemperature does not vary by more than X degrees across the coil, wherethe value of X may be preset. When the preset maximum temperature isexceeded or the analysis reveals that the temperature is not uniform,then there is a problem condition with the cartridge indicating either afaulty component or the need for calibration as described below withrespect to FIG. 6.

FIG. 6 is a diagram of a calibration process. In particular, thermalimaging may be used to calibrate a cartridge. The calibration can set amaximum power usage for a cartridge. In alternative embodiments, thecalibration may be used for determining that a particular, cartridge mayrequire more limited usage (e.g. a break time after continuous usage).The calibration process may begin with input conditions for the analyzerin block 602. In one embodiment, the input conditions may include amaximum temperature (at any location) and uniformity of temperaturerequired (e.g. limited variance of temperature). These input conditionsare used for the analysis of a particular cartridge to determine if thatcartridge may require calibration or adjustment of power usage foroptimal usage. In block 604, the e-Cig is connected with a pump toimitate inhalation. In one embodiment, a vacuum pump is on an oppositeend from the cartridge (e.g. battery portion) to “suck” air through thee-Cig. This inhalation imitation activates the e-Cig and the imagertakes an image that maps the temperature of the imaged region (e.g. theheating coil) in block 606. The analyzer compares this temperature mapwith the input conditions in block 608 to determine any potentialproblem conditions. If there are no problem conditions identified, thenthe input conditions are satisfied in block 612. However, if the inputconditions are not met, then the power parameters may be modified inblock 610. In one embodiment, the modification of power parametersincludes reducing the power provided to the cartridge. After the poweris slightly reduced, another image may be taken and compared as inblocks 606-608 and if the input conditions are still not met then theprocess is repeated of slightly reducing power and checking the thermalimage. After the input conditions are satisfied in block 612, the powerparameters (i.e. the last power value that satisfies the inputconditions) are established for the calibration in block 614. Thisparameter is then recorded with the cartridge for future usage in block616.

The calibration may be for the PWM scheme. In an alternative embodiment,The calibration may modify the duty cycle (% on time vs. % off time)such that the calibration may include a shut off time that may switchoff power periodically. For example, a particular cartridge may belimited to only 15 minutes of constant usage before requiring atemporary shut off. This may be in addition to or instead of thecalibration of the power level described above with respect to FIG. 6.The calibrated power scheme may also include dynamically varying regimenparameters as a function of the battery charge (i.e. voltage) or anyother complex energy management scheme.

The illustrations of the embodiments described herein are intended toprovide a general understanding of the structure of the variousembodiments. The illustrations are not intended to serve as a completedescription of all of the elements and features of apparatus and systemsthat utilize the structures or methods described herein. Many otherembodiments may be apparent to those of skill in the art upon reviewingthe disclosure. Other embodiments may be utilized and derived from thedisclosure, such that structural and logical substitutions and changesmay be made without departing from the scope of the disclosure.Additionally, the illustrations are merely representational and may notbe drawn to scale. Certain proportions within the illustrations may beexaggerated, while other proportions may be minimized. Accordingly, thedisclosure and the figures are to be regarded as illustrative ratherthan restrictive.

1. A method for quality control of an electronic cigarette comprising:powering a heating coil of the electronic cigarette; generating athermal image of the electronic cigarette that includes a representationof a temperature in the electronic cigarette; analyzing the thermalimage to identify temperature hot spot in the electronic cigarette; andcalibrating the electronic cigarette based on the analysis of thethermal image. 2.-20. (canceled)